Interior Karnataka Research Articles

On the rarity of the 2015 drought in India: A country-wide drought atlas using the multivariate standardized drought index and copula-based severity-duration-frequency curves

Study regionThe study is conducted over 30 meteorological sub-divisions of India. Study focusThe Multivariate Standardized Drought Index (MSDI) is employed to analyze the drought conditions caused by simultaneous precipitation and soil moisture deficiencies. The Severity-Duration-Frequency (SDF) relationships for the 30 sub-divisions are derived using copula-based conditional distribution for duration and severity; which are further used to prepare the country-wide drought atlas for different return periods. Subsequently, the developed atlas is used to assess the spatial extent and historical context of the impactful 2015 drought event. New hydrological insights for the regionThis is the first study to present a country-wide drought atlas for India, considering concurrent deficits in precipitation and soil moisture, and using copula-based SDF relationships. In general, drought characteristics such as severity and duration are found to be significantly correlated, highlighting the importance of their joint modeling for probabilistic risk assessment of droughts in India. The drought atlas reveals regions that are severely affected by the drought variability. The drought atlas developed here shows that the impactful 2015 drought event was severely deficient both in terms of precipitation and soil moisture. In particular, West Uttar Pradesh, East Uttar Pradesh, Jharkhand, Marathwada, Telangana and North Interior Karnataka sub-divisions are found to be under a very rare drought (probability of exceedance less than 10 %).

AGRICULTURAL DROUGHT AND SOIL MOISTURE ANALYSIS USING SATELLITE IMAGE BASED INDICES

Abstract. The deficiency in rainfall leads to meteorological droughts. Its manifestations are visible both in the vegetation cover and soil moisture. The present study assessed the characteristics of agricultural drought following meteorological droughts. The study also assessed the severity of meteorological droughts and their manifestation on the agriculture and soil moisture in a semi-arid area. The study has been carried out for the Malaprabha sub-basin which partly covers three districts of North Interior Karnataka, India. India Meteorological Department’s (IMD) criteria have been used to identify the drought years, and its severity has been assessed through the Standard Precipitation Index (SPI). The IMD’s monthly rainfall data were used to identify the drought years and periods for the region. Among the drought years, the mild, moderate, and severe drought along with deficit and excess rainfall years were considered to assess and characterize the soil moisture conditions and the agricultural drought. The satellite image based indices for these selected years were constructed to determine the soil moisture conditions and the agricultural drought severity. The Temperature-Vegetation Dryness Index (TVDI) was used to determine the soil moisture conditions. The indices employed to determine the agriculture drought are NDVI, Thermal Condition Index (TCI), Vegetation Condition Index (VCI), and Vegetation Health Index (VHI). These satellite-based indices were calculated using the Landsat images of the selected drought and non-drought years. The results showed that the seasonal and annual drought are frequent in the study area. There are spatial and temporal variations in the drought years and their severity. The satellite-based indices clearly indicate the spatial variation in the agriculture droughts and its intensity. It has been found that the impact of drought on agriculture has significantly reduced due to the development of well-irrigation in the sub-basin. VHI is more appropriate in determining the agricultural drought and its characteristics.

Estimating Extent of Vulnerability of Agriculture and Livelihoods to Climate Change

Vulnerability assessments can play a vital role in designing appropriate adaptation and mitigation policies targeted towards climate change and its impacts on ecosystems, and those who depend upon these resources for their livelihoods. This paper assesses climate change in Karnataka, the agriculture and livelihoods contexts of vulnerability. Karnataka state has the second largest area under rainfed agriculture in India and several studies have shown that climate change is happening in the state. Agriculture sector is vulnerable to climate variability and change across its three regions: coastal, hilly and plains.Long-period monthly rainfall data (1901-2016) at district, region and state level was collected from India Meteorological Department and other sources and changes in seasonal and annual rainfall are analyzed. A Principal Component Analysis (PCA) was run on a dataset of seven variables for agricultural vulnerability and ten variables for livelihood vulnerability across thirty districts. The PCA generated three components for each index that broadly represented the underlying themes of agriculture and livelihood vulnerability present in the larger data set. Two vulnerability indices i.e., agricultural vulnerability index and livelihood vulnerability index were developed for all districts.Long-period rainfall analysis showed a small decreasing trend in annual rainfall at the state level. South-eastern region is becoming slightly wetter, while parts of hilly region becoming drier. In one district, rainfall reduced by 460 mm and in the neighbour it raised by 250 mm. Decadal meteorological drought analysis indicated an increasing trend in moderate droughts in north interior Karnataka. Indicators like cropping intensity, gross area irrigated and commercial crop area are the major drivers in determining the agricultural vulnerability. Livelihood index indicators like per capita income, population density, percentage of literacy rate and livestock units are major drivers for livelihood vulnerability. Agricultural vulnerability index analysis indicates four districts and livelihood vulnerability index analysis shows five districts as most vulnerable.

Estimation of U, 226Ra, 210Po concentration in Cauvery river basin, south interior Karnataka Region, India

Estimation of U, 226Ra, 210Po concentration in Cauvery river basin, south interior Karnataka Region, India

Genomic characterization of coxsackievirus type B3 strains associated with acute flaccid paralysis in south-western India.

Acute flaccid paralysis (AFP) associated with coxsackievirus type B3 (CV-B3) of the species Enterovirus B is an emerging concern worldwide. Although CV-B3-associated AFP in India has been demonstrated previously, the genomic characterization of these strains is unreported. Here, CV-B3 strains detected on the basis of the partial VP1 gene in 10 AFP cases and five asymptomatic contacts identified from different regions of south-western India during 2009-2010 through the Polio Surveillance Project were considered for complete genome sequencing and characterization. Phylogenetic analysis of complete VP1 gene sequences of global CV-B3 strains classified Indian CV-B3 strains into genogroup GVI, along with strains from Uzbekistan and Bangladesh, and into a new genogroup, GVII. Genomic divergence between genogroups of the study strains was 14.4 % with significantly lower divergence (1.8 %) within GVI (n = 12) than that within GVII (8.5 %) (n = 3). The strains from both AFP cases and asymptomatic contacts, identified mainly in coastal Karnataka and Kerala, belonged to the dominant genogroup GVI, while the GVII strains were recovered from AFP cases in north interior Karnataka. All study strains carried inter-genotypic recombination with the structural region similar to reference CV-B3 strains, and 5' non-coding regions and non-structural regions closer to other enterovirus B types. Domain II structures of 5' non-coding regions, described to modulate virus replication, were predicted to have varied structural folds in the two genogroups and were attributed to differing recombination patterns. The results indicate two distinct genomic compositions of CV-B3 strains circulating in India and suggest the need for concurrent analysis of viral and host factors to further understand the varied manifestations of their infections.

Analysis of Rainfall in Assessing the Drought in Semi-arid Region of Karnataka State, India

The present study focuses on drought analysis with an aim to understand the drought vulnerability, estimate and map the drought duration and severity in drought prone North Interior Karnataka region, India. A detailed analysis were carried out using rainfall data of more than 178 (with greater than 30 years data) stations to understand the drought characteristics. Rainfall descriptive variability, percentage occurrence of drought incidences and spatial distribution of rainfall were derived. In order to evaluate the drought severity and its extent and to map, method proposed by Ponce et al. (2000) and the Geographic Information System has been used. The method by Ponce et al. (2000) characterize drought based on intensity, duration and recurrence interval using mean annual precipitation of a location. The results obtained for the study area indicate that, the region is mostly semi-arid with drought occur for more than 50 % of the time. The majority of the drought events are of moderate intensity with few extreme intensity events. Further, it is noticed that, in many station, the rainfall show a decreasing trend. Since, rainfall in this region are mostly declining due to climatic change, the area would experience increasing drought severity in the forthcoming years. The outcome of the study would be useful in understanding the drought pattern, severity and extent in the study area which can be used by scientists and water management professionals to plan drought mitigation measures.

226Ra and 210Po concentration in drinking water of Cauvery river basin south interior Karnataka State, India

Naturally occurring radionuclide 210Po which is an element of 238U decay series, contribute to the radiation that normally people are exposed. Drinking water samples collected from Cauvery river basin of south interior Karnataka State, India were analysed for the activity of 210Po using radiochemical analysis technique. The estimated concentration of 210Po in river water ranges from 0.86 to 4.49 mBq l−1, and its mean value is 2.67 ± 1.09 mBq l−1. The concentration of 210Po in bore well water ranges from 1.89 to 4.18 mBq l−1 and its mean value is 3.22 ± 0.67 mBq l−1. The dissolved radium concentration in river water varies from 9.09 mBq l−1 to 55.07 mBq l−1 with an average of 32.33 ± 14.16 mBq l−1. Total ingestion dose rate due to 226Ra and 210Po varies from 2.61 to 15.00 μSv y−1 with a mean value of 8.95 ± 3.74 μSv y−1, which is less than the recommended value by ICRP (International commission on radiological protection).

Monsoonal Droughts In India – A Recent Assessment

AbstractDrought frequencies during the years 1901–2010 were investigated over three spatial units – All India, 5 Homogeneous Regions (HR) and 36 Meteorological subdivisions (MSs). The All-India rainfall trend is in fact indicative of no trend, while the Northeast HR (NER) shows a significant decrease. Furthermore, a significant decrease in rainfallis to be observed over Himachal Pradesh, Madhya Pradesh, Maharashtra and the Southern Peninsular region, and a significant increase over West Bengal, Punjab, Haryana, Coastal Karnataka, North Interior Karnataka and Rayalaseema.There have been 21 All-India drought years during the last century, of which 13 were linked to El Niño. When compared with HRs, the WCR is highly prone to El Niño while the NER is not affected by this global tele-connection. Western Uttar Pradesh, Eastern Rajasthan, Uttarakhand, Vidharbha and Telangana shared 11–10 drought occasions with El Niño.Maximum frequencies of droughts (21) were reported for East Madhya Pradesh within the WCR and Orissa within the Central Northeast Region (CNER), while Andaman, Nicobar and Rayalaseema experienced minimum drought episodes (12) over the last century.Sixty percent of the MSs in the West Central Region (WCR) and the Northwest Region (NWR) were coherent with All-India droughts. During the years 1918, 1972 and 2002, the majority of HRs (except NER) witnessed normal or below-normal rainfall. Western Madhya Pradesh within the WCR saw maximum drought events (13). The highest degree of simultaneous occurrence of drought years between the MSs and all-India concern Eastern Rajasthan, Western Madhya Pradesh, East and West Uttar Pradesh. The study also found that the MSs in HRs highly affected are East Rajasthan (NWR), West Madhya Pradesh (WCR), West and East Uttar Pradesh (CNER), NER and Coastal Karnataka (Peninsular Region). Western Uttar Pradesh, Eastern Rajasthan, Vidarbha and Telangana had 10–11 occasions when El Niño and Drought years occurred.

A study of variations of sacral hiatus of dry human sacra in north interior Karnataka region

Abstract Background and aims: The shape of sacral hiatus is known to show a number of anatomical variations. The shape and extent of sacral hiatus is important because in caudal epidural anaesthesia, the approach is made through sacral hiatus. The detailed anatomical knowledge of variations of sacral hiatus is very helpful to the anaesthetists to increase the success rate of caudal anaesthesia. The present study is an attempt to find out variations of sacral hiatus in north interior Karnataka region. Materials and methods: For the present study, one hundred dry human sacra obtained from north interior Karnataka region were used. Results: The inverted U shaped sacral hiatus was most common (56%). Inverted V shaped sacral hiatus was found in 24% of sacra. The other variations like irregular shaped hiatus (10%), bifid hiatus (2%), dumbbell shaped hiatus (5%), complete spina bifida (1%) and absent hiatus (2%) were also found. Conclusion: Abnormal shapes of sacral hiatus like irregular, bifid, dumbbell, completespina bifida and absent hiatus were seen in 20%of total 100 sacra belonging to north interior Karnataka.

Dry spell characteristics over India based on IMD and APHRODITE datasets

Selected characteristics of dry spells and associated trends over India during the 1951–2007 period is studied using two gridded datasets: the Indian Meteorological Department (IMD) and the Asian Precipitation-Highly Resolved Observational Data Integration Towards Evaluation of the water resources (APHRODITE) datasets. Two precipitation thresholds, 1 and 3 mm, are used to define a dry day (and therefore dry spells) in this study. Comparison of the spatial patterns of the dry spell characteristics (mean number of dry days, mean number of dry spells, mean and maximum duration of dry spells) for the annual and summer monsoon period obtained with both datasets agree overall, except for the northernmost part of India. The number of dry days obtained with APHRODITE is larger for this region compared to IMD, which is consistent with the smaller precipitation for the region in APHRODITE. These differences are also visible in the spatial patterns of mean and maximum dry spell durations. Analysis of field significance associated with trends, at the level of 34 predefined meteorological subdivisions over the mainland, suggests better agreement between the two datasets in positive trends associated with number of dry days for the annual and summer monsoon period, for both thresholds. Important differences between the two datasets are noted in the field significance associated with the negative trends. While negative trends in annual maximum duration of dry spells appear field significant for the desert regions according to both datasets, they are found field significant for two regions (Punjab and South Interior Karnataka) for the monsoon period for both datasets. This study, in addition to providing information on the spatial and temporal patterns associated with dry spell characteristics, also allows identification of regions and characteristics where the two datasets agree/disagree.

A study of variations of sacral hiatus of dry human sacra in north interior Karnataka region

Background and aims: The shape of sacral hiatus is known to show a number of anatomical variations. The shape and extent of sacral hiatus is important because in caudal epidural anaesthesia, the approach is made through sacral hiatus. The detailed anatomical knowledge of variations of sacral hiatus is very helpful to the anaesthetists to increase the success rate of caudal anaesthesia. The present study is an attempt to find out variations of sacral hiatus in north interior Karnataka region. Materials and methods: For the present study, one hundred dry human sacra obtained from north interior Karnataka region were used. Results: The inverted U shaped sacral hiatus was most common (56%). Inverted V shaped sacral hiatus was found in 24% of sacra. The other variations like irregular shaped hiatus (10%), bifid hiatus (2%), dumbbell shaped hiatus (5%), complete spina bifida (1%) and absent hiatus (2%) were also found. Conclusion: Abnormal shapes of sacral hiatus like irregular, bifid, dumbbell, completespina bifida and absent hiatus were seen in 20% of total 100 sacra belonging to north interior Karnataka.

Study of winter fog over Indian subcontinent : Climatological perspectives

Fog is localized phenomenon where horizontal visibility is reduced to less than 1000 m due to suspension of very small water droplets in the air. In fact Fog is cloud at surface level. This phenomenon matters to us in our daily activities due to its effect on life, public health, road safety, and economic prosperity. Its knowledge is essential to meet critical societal needs. In India, radiation and advection fog are most common which occur mostly over north India in winter. This study presents results of spatial variability of average number of days having visibility less than 1000 m at 0300 UTC during winter season over Indian subcontinent (0° N-35° N and 60° E-100° E) using synoptic hour daily surface data. Analysis of Fog events based on half hourly METAR observations for winter months (December 2010-February 2011) at selected ICAO stations of India is also presented.
 
 The monthly spatial variability of average number of days with fog having visibility less than 1000 m indicates presence of fog over Indo-Gangetic plains on an average of 7 to 10 days during December and more than 8 days during January. South Gangetic West Bengal is susceptible to fog during February. Seasonal variation of fog shows that there is prominence of fog over Indo-Gangetic plains on an average of more than 6.5 days. Significant incidences of foggy days occur over South Interior Karnataka and Coastal Karnataka has incidence of foggy days on an average of 6.5 days. North India is susceptible to dense fog on average of 2.5 days during the season while Gangetic West Bengal, West Rajasthan and adjoining parts of east Rajasthan and East Uttar Pradesh have occurrence of fog on an average of 3.5 days. Thick fog occurs on an average of 3 days over northern India during the winter season. Analysis of time series of air temperature, dew point temperature, dew point depression, visibility, zonal and meridional components of wind and its magnitude at selected ICAO stations indicate that visibility reduces to below 1000 m while light winds are southeasterly at Ahmedabad, northerly to northwesterly at Amritsar, northerly to northeasterly at New Delhi, westerly to southwesterly at Kolkata, Guwahati and dew point depression is below 3 °C during such conditions. Long period 1971-2010 analysis of visibility conditions less than 1000 m over Indian subcontinent shows Indo-Gangetic plains region to have average wind speed to be 0.6 m/s, air temperature in the range 9 °C to 15 °C during December-February at 0300 UTC. Long period 1971- 2010 analysis of relative humidity shows Indo-Genetic plains region to have relative humidity in the range 72% to 84% at 0300 UTC during December-February.

Cumulonimbus cloud with anvil over India : Synoptic cloud type observations 1970-2000

The features of observational aspects of frequencies of occurrence of Cb clouds with anvil over India have been presented. Synoptic cloud type observations for 101 uniformly distributed Class I surface observatories of India Meteorological Department for pre-monsoon months for period 1970-2000 is taken.
 The results reveal that the formation of Cb clouds with anvil exhibit the diurnal tendency of growth of cloud areas and show drastic decrease in the early morning hours. The temporal evolution of Cb clouds with anvil show that during the period from 0900 UTC to 2100 UTC, the maximum peak of convective cloud activity occur at 1200 UTC. This study has brought forth five prominent belts of Cb clouds prevalence showing both temporal and spatial characteristics during the month of May which is the month of peak thunderstorm activity. The first belt extends from South peninsula along West Coast of India covering regions of Kerala, Tamil Nadu and Puducherry, South Interior Karnataka, Coastal Karnataka, parts of North Interior Karnataka, Konkan and Goa, Madhya Maharashtra and West Madhya Pradesh (3 to 10 days). The region South Interior Karnataka and adjoining Kerala and Tamil Nadu has reported Cb clouds with anvil to be about 10 days. The second belt comprises Himachal Pradesh and adjoining Jammu & Kashmir, Uttarakhand and adjoining West UP. The third belt covers spatial areas of Chhattisgarh and adjoining Vidharbha, Orissa, Gangetic West Bengal and adjoining areas of Jharkhand and Bihar. The fourth belt is SHWB, Assam and Meghalaya covering Guwahati and Shillong. The fifth belt comprises regions of Tripura and adjoining Mizoram. The rest of Northeast India report Cb clouds with anvil on the average of 1 to 3 days. The region South Bihar and adjoining Jharkhand and Gangetic West Bengal report Cb clouds with anvil on the average of 5 to 7 days.

SPATIAL PATTERN OF TEMPORAL TREND OF CROP PHENOLOGY MATRICES OVER INDIA USING TIMESERIES GIMMS NDVI DATA (19826ndash;2006)

Abstract. NOAA-AVHRR bi-monthly NDVI data of 8×8 km for the period of 1982–2006 were used to analyze the trend of crop phenology matrices over Indian region. Time series principal component analysis of NDVI was performed to produce six calibration zones for fitting equations of temporal NDVI profile. Savitzky-Golay filter with different seasonality parameters, adaptation strengths and window sizes for different calibration zones were use to smoothen the NDVI profile. Three crop phenology matrices i.e. start of the growing season (SGS), Seasonal NDVI amplitude (AMP), Seasonally Integrated NDVI (SiNDVI) were extracted using TIMESAT software. Direction and magnitude of trends of these crop phenology matrices were analyzed at pixel level using Mann-Kendall test. Further the trends was assessed at meteorological subdivisional level using "Field significance test". Significant advancement of SGS was observed over Punjab, Haryana, Marathwada, Vidarbha and Madhya Maharashtra where as delay was found over Rayalaseema, Coastal Andhra Pradesh, Bihar, Gangetic West Bengal and Sub-Himalayan West Bengal. North, West and central India covering Punjab, Haryana, West & East Uttar Pradesh, West & East Rajasthan, West & East Madhya Pradesh, Sourastra & Kutch, Rayalaseema, Marathwada, Vidarbha, Bihar and Sub-Himalayan West Bengal showed significant greening trend of kharif season. Most of the southern and eastern part of India covering Tamilnadu, South Interior Karnataka, Coastal Andhra Pradesh, Madhya Maharashtra, Gujarat region, Chhattisgarh, Jharkhand and Gangetic West Bengal showed significant browning trend during kharif season.

Floods in Karnataka during 2009 : A synoptic study

Karnataka a State in south peninsular India receives 73% of its annual rainfall during southwestmonsoon season. Because of the complex physiographical features, the rainfall pattern over the State shows large spatialvariation from 50 to 350 cms. The coefficient of interannual variation of the monsoon rainfall is about 15% over coastalKarnataka (CK) and between 20-30% over interior Karnataka. The precipitation over this State is mainly dominated bysemi permanent systems like off shore trough running along the west coast, low pressure systems forming over the Bay ofBengal during the monsoon season. A well marked low pressure area during 28 September - 3 October 2009 over the Bayof Bengal caused widespread damage to life and property in north Karnataka. In this study, an attempt has been made toexamine the synoptic features of this system that caused heavy rainfall over many districts of the State leading towidespread destruction.

District-wide drought climatology of the southwest monsoon season over India based on standardized precipitation index (SPI)

District-wide drought climatology over India for the southwest monsoon season (June–September) has been examined using two simple drought indices; Percent of Normal Precipitation (PNP) and Standardized Precipitation Index (SPI). The season drought indices were computed using long times series (1901–2003) of southwest monsoon season rainfall data of 458 districts over the country. Identification of all India (nation-wide) drought incidences using both PNP and SPI yielded nearly similar results. However, the district-wide climatology based on PNP was biased by the aridity of the region. Whereas district-wide drought climatology based on SPI was not biased by aridity. This study shows that SPI is a better drought index than PNP for the district-wide drought monitoring over the country. SPI is also suitable for examining break and active events in the southwest monsoon rainfall over the country. The trend analysis of district-wide season (June–September) SPI series showed significant negative trends over several districts from Chattisgarh, Bihar, Kerala, Jharkhand, Assam and Meghalaya, Uttaranchal, east Madhya Pradesh, Vidarbha etc., Whereas significant positive trends in the SPI series were observed over several districts from west Uttar Pradesh, west Madhya Pradesh, South & north Interior Karnataka, Konkan and Goa, Madhya Maharashtra, Tamil Nadu, East Uttar Pradesh, Punjab, Gujarat etc.

Prediction of occurrence of daily summer monsoon precipitation over Karnataka

AbstractKarnataka, a State in south peninsular India, receives 73% of its annual rainfall during the southwest monsoon season. Because of the complex physiographical features, the rainfall pattern over the State shows large spatial variation from 50 to 350 cm. The coefficient of interannual variation of the monsoon rainfall is about 15% over coastal Karnataka (CK) and between 20 and 30% over interior Karnataka. It is, therefore, a difficult task to predict the location specific daily rainfall over Karnataka. In this study, an attempt has been made to develop an objective tool for forecasting the occurrence and non‐occurrence of precipitation during a 24 h period for the 19 stations in Karnataka during the monsoon season. The probability of precipitation (POP) model is developed using forward stepwise regression with the available surface and upper air parameters from synoptic and radiosonde and radio wind stations in and around Karnataka as potential predictors. The POP model has been developed based on the data from 1981 to 1996 and verified with the data from 1997 to 2002. Different skill scores are computed using a yes/no contingency table. The POP model performs very well, with percentages of correct (PC) forecasts for occurrence/non‐occurrence of precipitation being 57–91% for the independent data. Comparing the results of the POP model with that of the conventional method of forecast for Bangalore City, the PC forecasts improves from 44 to 56% with the use of the POP model. Copyright © 2011 Royal Meteorological Society

Study of crop condition and assessment of agricultural drought in rabi season using IRS – AWiFS images

Although kharif season crops are more vulnerable to agricultural droughts due to uncertainty in monsoon rains, crops of rabi season grown under residual soil moisture and rainfed minor irrigation tanks are equally vulnerable to drought hazard. The present study was undertaken in Bagalkot district of north interior Karnataka to assess the extent of crop area affected by agricultural drought during rabi 2005-06, using Advanced Wide Field Sensor (AWiFS) images of Indian Remote Sensing Satellite, Resourcesat-1. Normalised Difference Vegetation Index (NDVI) images which represent density, health and vigour of crops were generated from satellite images and analyzed in association with cropping pattern, crop calendar, rainfall pattern and soil depth. The area affected by agricultural drought was delineated in each taluk. The study indicated the feasibility for detailed assessment of agricultural drought during rabi season on near real-time basis using the indigenously available AWiFS images.

Trends in the rainfall pattern over India

AbstractNew monthly, seasonal and annual rainfall time series of 36 meteorological subdivisions of India were constructed using the monthly rainfall data for the period 1901–2003 of fixed network of 1476 rain gauge stations. In the new network, on an average, there is one rain gauge station for every 3402 Sq km area. The new rainfall series is temporally as well as spatially homogenous. Linear trend analysis was carried out to examine the long‐term trends in rainfall over different subdivisions and monthly contribution of each of the monsoon months to annual rainfall. During the south‐west monsoon season, three subdivisions viz. Jharkhand, Chattisgarh, Kerala showed significant decreasing trend and eight subdivisions viz. Gangetic WB, West UP, Jammu and Kashmir, Konkan and Goa, Madhya Maharashtra subdivision, Rayalseema, Coastal AP and North Interior Karnataka showed significant increasing trends. It has been found that the contribution of June, July and September rainfall to annual rainfall is decreasing for few subdivisions while contribution of August rainfall is increasing in few other subdivisions. EOF analysis is also done to know the spatial distribution of rainfall. The all India Monthly, seasonal and annual rainfall series constructed based on the 1476 stations are also reported. Copyright © 2007 Royal Meteorological Society

Predatory Efficiency of Mallada astur (Banks), a Chrysopid Predator of Coconut Leafeating Caterpillar, Opisina arenosell a Walker

The chrysopid, Mallada astur (Banks), recorded for the first time as promising egg and early larval predator of O. arenosella in interior Karnataka was evaluated for its predatory efficiency. This predator is predominant on coconut and palmyrah palms of 30m height. Its short life cycle (24.5 days) on a combined diet of eggs and larvae of O. arenosella , high fecundity per female (mean=102.3 eggs), and its ability to thrive in the larval galleries of O. arenosella , strongly support its utilization as a biocontrol agent during peak period of infestation (September-February) in interior Karnataka. Net house studies revealed that release of one M. astur larva (4 day old) per severely infested leaflet with about 35·50 neonate larvae will effectively reduced the population of the pest within a week.